The need for an efficient and economic intermodal transport system has been recognized throughout the rail industry, but to date a system does not exist which can provide the many advantages inherent in the instant invention. One type of system, described in U.S. Pat. No. 4,385,857 to the instant inventor, is directed to an intermodal transport system and provides many advantages previously unrecognized by the rail industry. In the system described in U.S. Pat. No. 4,385,857, damage free shipments with reduced loads per axle and unrestricted main line clearances through tunnels are facilitated by method and apparatus which utilize an intregal interchange where trailer containers, whose adjacent ends are supported vertically for linehaul at upstanding king pins, integral with centerplates suspended in tandem axle rail support trucks, are assembled into, or broken from train formation to transfer containers and trailers by means of elevating shuttle means.
In that system, trailer containers are transported over rail on a plurality of rail trucks, with each container being supported by centerplates on each of the rail trucks and the containers interfacing with the centerplates through upstanding king pins to provide easy assembly into a train formation configuration. The system described in U.S. Pat. No. 4,385,857 eliminates the necessity for utilizing flat cars to transport trailer containers and utilizes a unique suspension system which permits damage free shipments with the most fragile cargo.
Notwithstanding the advantages provided by the system described in U.S. Pat. No. 4,385,857 that system does require an interchange facility for operation. The present invention takes advantage of the teachings in this U.S. Patent, but eliminates the necessity to utilize a different, and currently not existing, interchange system. Rather, the present invention utilizes standard ground based cranes which have been in use for a number of years in the Piggyback system for transferring highway trailer containers, and/or ship containers, to rail transportation. With a lift crane at every interchange, car coupling is accomplished vertically, instead of horizontally, as obtained with a standard jaw coupler, with the exception of the ends where the locomotive and caboose are attached. In addition, the system described in U.S. Pat. No. 4,385,857 requires fifteen foot height for operation, which is an improvement over the seventeen foot overhead clearance required for flt car operations, but still would not be able to operate on locations with overhead clearances being less than the fifteen feet. The instant invention substantially reduces the overhead clearance necessary for rail transport of trailer containers.
It is, therefore, a general object of the instant invention, to provide a train of low profile intermodal rail hardware which only requires an overhead clearance of approximately thirteen feet, six inches.
It is another object of the instant invention to provide an intermodal transport system which utilizes standard ground based lift cranes for interchange of sea or highway containers to rail lines, but yet provides significant economic advantages over the present Piggyback system.
It is a further object of the instant invention to provide an intermodal transport system wherein the use of jaw couplers is not required (except at train ends) and wherein novel support structure couples the ends of rail trucks together, provides slack for starting the train, absorbs buffing shocks and prevents torsional strains.